The present invention relates to a support structure for supporting a concrete placing boom at a work site. More specifically, the present invention relates to a support structure that includes an adapter that is removably attachable to a support mast and receives the concrete placing boom such that a single adapter can be used with multiple support masts.
Currently, concrete placing booms are used at large work sites, such as in the construction of a multi-floored building, for placing concrete in hard to access locations. Typically, the concrete placing boom is mounted to a support structure that extends above the working surface such that concrete can be supplied from above without requiring heavy hoses to be dragged over the deck, reinforcing and post tensioning cables.
In a large work site, multiple support masts or towers are constructed such that the concrete placing boom can be moved from one support tower to the next in order to provide the required coverage area for the structure being created. In currently available support structures for the concrete placing boom, an adapter is integrally formed with each of the towers or support masts. Each adapter is sized to receive a pedestal formed on the concrete placing boom. An overhead crane is used to move the concrete placing boom and pedestal above the adapter until the concrete placing boom can be lowered into contact with the adapter. Once in contact with the adapter integrally formed with the support mast, the pedestal can be secured to the adapter and support mast.
In several currently available support systems, each of the support masts or towers includes its own adapter secured to the tower. Since each adapter is a large and heavy structure, it is possible that several adapters located at each work site are not being used at any given time.
The support masts or towers in the currently available systems include numerous projections used to secure the mast within a concrete floor opening. However, the projections can contact the floor opening and damage the opening when the support mast is moved from one floor to another. Thus, additional care must be taken when moving the prior art support structure from one location to another, which increases the time needed to move the equipment.
Therefore, a need exists for a support structure for a concrete placing boom in which an adapter is removably attachable to each of the support masts or towers positioned at the work site. Further, a need exists for an adapter that can be removed from one of the support masts and attached to another support mast through a simple mounting arrangement. Additionally, a need exists for an adapter that is received upon the support mast and includes a self-aligning feature to ensure the proper connection of the adapter to the support mast. Further, a need exists for a support mast that does not include external projection to decrease the care required to move the support mast between floors of a building being constructed.
The present invention relates to a support structure for supporting a concrete placing boom above a work site such that the concrete placing boom can supply a flow of concrete to a particular work position. The support structure of the present invention includes a plurality of individual support masts positioned about the work site. Each of the support masts extends above and is supported by a support surface. For example, each support mast can be supported on and by a lower floor of a building being constructed.
Each support mast is a generally cylindrical structure having an outer wall defining a generally hollow interior. The outer wall of the support mast has an outer surface that is generally devoid of any external projections. The smooth outer surface of the support mast allows the mast to be efficiently manufactured and moved longitudinally with respect to an opening formed in the support surface.
The support mast is closed at its top end by a top plate. The top plate of each support mast includes a central guide opening that aids in locating the center of the support mast.
The support structure of the present invention further includes an adapter that is removably mountable to any one of the plurality of support masts positioned around the work site. The adapter includes a boom attachment portion configured to receive the mounting pedestal of the concrete placing boom and a mast receiving portion that is configured to receive the respective support mast. In this manner, the adapter can be removably attached to both the concrete placing boom and the support mast. Thus, only one adapter is required for the entire support structure of the invention.
The boom attachment portion of the adapter includes a top support plate mounted to the top end of the adapter. The top support plate provides the required support for a series of inner and outer lugs. The inner and outer lugs are spaced from each other to receive depending ears formed on the pedestal of the concrete placing boom. When the concrete placing boom is lowered onto the adapter, the ears of the pedestal are positioned between one of the inner lugs and one of the outer lugs and an attachment bolt secures the adapter to the pedestal.
The mast receiving portion of the adapter is defined at its top end by a mast support plate that is positioned within the interior of the adapter. The mast support plate is secured to the inner surface of the cylindrical wall forming the body portion of the adapter. When the adapter is lowered into contact with the mast, the top end of the mast contacts the mast support plate such that the adapter is supported on the mast by the mast support plate.
The mast support plate includes a guide pin that is sized to fit into the mast receiving receptacle. The guide pin includes a tapered lower surface that is sized to be received within the central guide opening formed on the top end of the mast. The interaction between the guide pin and the central guide opening formed in the top plate of the mast aids in guiding the proper alignment between the adapter and the mast.
Once the adapter is positioned on the respective mast, a pressure coupling contained on the mast receiving portion of the adapter is tightened to secure the adapter to the mast. In the preferred embodiment of the invention, the pressure coupling includes a plurality of adjustment screws that can be tightened into contact with the outer surface of the mast. Preferably, a strengthening plate is mounted within the mast and aligned with the contact points between the pressure coupling and the masts. In this manner, the strengthening plate provides further support for the outer wall of the mast.
The removable adapter of the present invention allows the adapter to be removed from one support mast and reinstalled on a second support mast. Thus, only a single adapter is required for a work site having multiple support masts. Since the adapter is a substantial structure, the inclusion of only one adapter in the support structure of the invention significantly reduces the cost of the overall system.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.